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Topic Review
Mass Concentration
In chemistry, the mass concentration ρi (or γi) is defined as the mass of a constituent mi divided by the volume of the mixture V. For a pure chemical the mass concentration equals its density (mass divided by volume); thus the mass concentration of a component in a mixture can be called the density of a component in a mixture. This explains the usage of ρ (the lower case Greek letter rho), the symbol most often used for density.
  • 3.1K
  • 12 Oct 2022
Topic Review
Coffee Berry Borer (Hypothenemus hampei)
Coffee berry borer (CBB) is the most serious insect pest of coffee worldwide, causing more than US$500M in damages annually. Reduction in the yield and quality of coffee results from the adult female CBB boring into the coffee fruit and building galleries for reproduction, followed by larval feeding on the bean itself.
  • 3.1K
  • 23 Dec 2020
Topic Review
UI GreenMetric and Sustainability at Universities
The concept of sustainability has become more important, especially as a result of the depletion of energy resources and increasing environmental concerns. UI GreenMetric ranks universities based on sustainability, environmental, and energy concerns, addressing issues of environmental pollution, food and water scarcity, and energy supply.
  • 3.1K
  • 21 Aug 2023
Topic Review
Polyphenylsulfone Membrane
Polyphenylsulfone (PPSU) membranes are of fundamental importance for many applications such as water treatment, gas separation, energy, electronics, and biomedicine, due to their low cost, controlled crystallinity, chemical, thermal, and mechanical stability. Numerous research studies have shown that modifying surface properties of PPSU membranes influences their stability and functionality. Therefore, the modification of the PPSU membrane surface is a pressing issue for both research and industrial communities.
  • 3.1K
  • 10 Mar 2022
Topic Review
Phytochemicals in Daucus carota
Carrots are a multi-nutritional food source. They are an important root vegetable, rich in natural bioactive compounds, which are recognised for their nutraceutical effects and health benefits.
  • 3.1K
  • 07 Jul 2021
Topic Review
Great Oxygenation Event
The Great Oxygenation Event, the beginning of which is commonly known in scientific media as the Great Oxidation Event (GOE, also called the Oxygen Catastrophe, Oxygen Crisis, Oxygen Holocaust, Oxygen Revolution, or Great Oxidation) was the biologically induced appearance of dioxygen (O2) in Earth's atmosphere. Geological, isotopic, and chemical evidence suggests that this major environmental change happened around 2.45 billion years ago (2.45 Ga), during the Siderian period, at the beginning of the Proterozoic eon. The causes of the event remain unclear. (As of 2016), the geochemical and biomarker evidence for the development of oxygenic photosynthesis before the Great Oxidation Event has been mostly inconclusive. Oceanic cyanobacteria, which evolved into coordinated (but not multicellular or even colonial) macroscopic forms more than 2.3 billion years ago (approximately 200 million years before the GOE), are believed to have become the first microbes to produce oxygen by photosynthesis. Before the GOE, any free oxygen they produced was chemically captured by dissolved iron or by organic matter. The GOE started when oxygen produced by the cyanobacteria started escaping into the atmosphere, after other oxygen reservoirs were filled. The increased production of oxygen set Earth's original atmosphere off-balance. Free oxygen is toxic to obligate anaerobic organisms, and the rising concentrations may have destroyed most such organisms at the time. A spike in chromium contained in ancient rock-deposits formed underwater shows the accumulation had been washed off from the continental shelves. Chromium is not easily dissolved and its release from rocks would have required the presence of a powerful acid. One such acid, sulfuric acid (H2SO4), might have formed through bacterial reactions with pyrite. Mats of oxygen-producing cyanobacteria can produce a thin layer, one or two millimeters thick, of oxygenated water in an otherwise anoxic environment even under thick ice; before oxygen started accumulating in the atmosphere, these organisms would already have adapted to oxygen. Additionally, the free oxygen would have reacted with atmospheric methane, a greenhouse gas, greatly reducing its concentration and triggering the Huronian glaciation, possibly the longest episode of glaciation in Earth's history and called "snowball Earth". Eventually, the evolution of aerobic organisms that consumed oxygen established an equilibrium in its availability. Free oxygen has been an important constituent of the atmosphere ever since.
  • 3.1K
  • 10 Nov 2022
Topic Review
Structure-Based Drug Design
The functionality of a protein is dependent upon its structure, and structure-based drug design (SBDD) relies on the 3D structural information of the target protein, which can be acquired from experimental methods, such as X-ray crystallography, NMR spectroscopy and cryo-electron microscopy (cryo-EM). The aim of SBDD is to predict the Gibbs free energy of binding (ΔGbind), the binding affinity of ligands to the binding site, by simulating the interactions between them.
  • 3.1K
  • 09 Jan 2023
Topic Review
Implementation of Lutetium-177 Therapy
Peptide receptor radionuclide therapy (PRRT) using Lutetium-177 (177Lu) based radiopharmaceuticals has emerged as a therapeutic area in the field of nuclear medicine and oncology, allowing for personalized medicine. Since the first market authorization in 2018 of [¹⁷⁷Lu]Lu-DOTATATE (Lutathera®) targeting somatostatin receptor type 2 in the treatment of gastroenteropancreatic neuroendocrine tumors, intensive research has led to transfer innovative 177Lu containing pharmaceuticals to the clinic.
  • 3.1K
  • 04 May 2023
Topic Review
Organic Fouling
Organic fouling in the forward osmosis process is complex and influenced by different parameters in the forward osmosis such as type of feed and draw solution, operating conditions and type of membrane. In this article, we reviewed organic fouling in the forward osmosis focussing on wastewater treatment applications. Model organic foulants used in the forward osmosis literature were highlighted, followed by the characteristics of organic foulants when real wastewater are used as feed solutions. The present study evaluated various physical and chemical cleaning protocols for organic fouled membrane and the efficiency of cleaning methods for the removal of organic fouling in the forward osmosis process. The study made recommendations on future cleaning technologies such as Ultraviolet and Ultrasound. Generally, a combination of physical and chemical cleaning is the best for restoring the water flux in the FO process.
  • 3.1K
  • 27 Oct 2020
Topic Review
Lazarus (IDE)
Lazarus is a free cross-platform visual integrated development environment (IDE) for rapid application development (RAD) using the Free Pascal compiler. Its goal is to provide an easy-to-use development environment for programmers developing with the Pascal Object language, which is as close as possible to Delphi. Software developers use Lazarus to create native-code console and graphical user interface (GUI) applications for the desktop, and also for mobile devices, web applications, web services, visual components and function libraries for a number of different platforms, including Mac, Linux and Windows. An application created using Lazarus on one platform can generally compile and execute on any platform for which a Free Pascal compiler exists. For desktop applications a single source can target Mac, Linux, and Windows, with little or no modification. An example is the Lazarus IDE itself, created from a single code base and available on all major platforms including the Raspberry Pi.
  • 3.1K
  • 30 Sep 2022
Topic Review
Applications and Action Mechanisms of Probiotic-Based Multi-Components
Probiotic-based multi-component preparations refer to a mixture of bioactive agents, containing probiotics or postbiotics as main functional ingredients, and prebiotics, protectants, stabilizers, encapsulating agents, and other compounds as additional constituents.
  • 3.1K
  • 13 Sep 2022
Topic Review
Sodium Cyclamate
Sodium cyclamate (sweetener code 952) is an artificial sweetener. It is 30–50 times sweeter than sucrose (table sugar), making it the least potent of the commercially used artificial sweeteners. It is often used with other artificial sweeteners, especially saccharin; the mixture of 10 parts cyclamate to 1 part saccharin is common and masks the off-tastes of both sweeteners. It is less expensive than most sweeteners, including sucralose, and is stable under heating. Safety concerns led to it being banned in a few countries, though the European Union considers it safe.
  • 3.1K
  • 08 Oct 2022
Topic Review
Cytokinins in Horticultural Fruit Crops
Cytokinins (CKs) are a chemically diverse class of plant growth regulators, exhibiting wide-ranging actions on plant growth and development, hence their exploitation in agriculture for crop improvement and management. Their coordinated regulatory effects and cross-talk interactions with other phytohormones and signaling networks are highly sophisticated, eliciting and controlling varied biological processes at the cellular to organismal levels. In this review, we briefly introduce the mode of action and general molecular biological effects of naturally occurring CKs before highlighting the great variability in the response of fruit crops to CK-based innovations. We present a comprehensive compilation of research linked to the application of CKs in non-model crop species in different phases of fruit production and management. By doing so, it is clear that the effects of CKs on fruit set, development, maturation, and ripening are not necessarily generic, even for cultivars within the same species, illustrating the magnitude of yet unknown intricate biochemical and genetic mechanisms regulating these processes in different fruit crops. Current approaches using genomic-to-metabolomic analysis are providing new insights into the in planta mechanisms of CKs, pinpointing the underlying CK-derived actions that may serve as potential targets for improving crop-specific traits and the development of new solutions for the preharvest and postharvest management of fruit crops. Where information is available, CK molecular biology is discussed in the context of its present and future implications in the applications of CKs to fruits of horticultural significance.
  • 3.1K
  • 27 Aug 2020
Topic Review
Almond By-Products
Almond (Prunus dulcis(Mill.) D. A. Webb, Prunus amygdalus Batch, or Amygdalus communis L.) constitutes the most produced nut worldwide, thanks to its exceptional nutritional composition, including low sugar content, high levels of proteins, unsaturated fatty acids, vitamins, and minerals, as well as health-enhancing phytochemicals.
  • 3.1K
  • 18 Aug 2021
Topic Review
Position and Momentum Space
In physics and geometry, there are two closely related vector spaces, usually three-dimensional but in general could be any finite number of dimensions. Position space (also real space or coordinate space) is the set of all position vectors r in space, and has dimensions of length. A position vector defines a point in space. If the position vector of a point particle varies with time it will trace out a path, the trajectory of a particle. Momentum space is the set of all momentum vectors p a physical system can have. The momentum vector of a particle corresponds to its motion, with units of [mass][length][time]−1. Mathematically, the duality between position and momentum is an example of Pontryagin duality. In particular, if a function is given in position space, f(r), then its Fourier transform obtains the function in momentum space, φ(p). Conversely, the inverse Fourier transform of a momentum space function is a position space function. These quantities and ideas transcend all of classical and quantum physics, and a physical system can be described using either the positions of the constituent particles, or their momenta, both formulations equivalently provide the same information about the system in consideration. Another quantity is useful to define in the context of waves. The wave vector k (or simply "k-vector") has dimensions of reciprocal length, making it an analogue of angular frequency ω which has dimensions of reciprocal time. The set of all wave vectors is k-space. Usually r is more intuitive and simpler than k, though the converse can also be true, such as in solid-state physics. Quantum mechanics provides two fundamental examples of the duality between position and momentum, the Heisenberg uncertainty principle ΔxΔp ≥ ħ/2 stating that position and momentum cannot be simultaneously known to arbitrary precision, and the de Broglie relation p = ħk which states the momentum and wavevector of a free particle are proportional to each other. In this context, when it is unambiguous, the terms "momentum" and "wavevector" are used interchangeably. However, the de Broglie relation is not true in a crystal.
  • 3.1K
  • 24 Nov 2022
Topic Review
Thyme
A perennial wild shrub from the Lamiaceae family and native to the Mediterranean region, thyme is considered an important wild edible plant studied for centuries for its unique importance in the food, pharmaceutical, and cosmetic industry. Thyme is loaded with phytonutrients, minerals and vitamins. It is pungent in taste, yet rich in moisture, proteins, crude fiber, minerals and vitamins. Its chemical composition may vary with geographical location but is mainly composed of flavonoids and antioxidants.
  • 3.1K
  • 07 Jun 2022
Topic Review
Commonwealth
A commonwealth is a traditional English term for a political community founded for the common good. Historically it has sometimes been synonymous with "republic". The noun "commonwealth", meaning "public welfare general good or advantage", dates from the 15th century. Originally a phrase (the common-wealth or the common wealth – echoed in the modern synonym "public wealth") it comes from the old meaning of "wealth", which is "well-being", and is itself a loose translation of the Latin res publica (republic). The term literally meant "common well-being". In the 17th century, the definition of "commonwealth" expanded from its original sense of "public welfare" or "commonweal" to mean "a state in which the supreme power is vested in the people; a republic or democratic state". The term evolved to become a title to a number of political entities. Three countries – Australia , the Bahamas, and Dominica – have the official title "Commonwealth", as do four U.S. states and two U.S. territories. Since the early 20th century, the term has been used to name some fraternal associations of nations, most notably the Commonwealth of Nations, an organization primarily of former territories of the British Empire, which is often referred to as simply "the Commonwealth".
  • 3.1K
  • 10 Nov 2022
Topic Review
Strategic Mining Options Optimization
 It is important that the strategic mine plan makes optimum use of available resources and provides continuous quality ore to drive sustainable mining and profitability. This requires the development of a well-integrated strategy of mining options for surface and/or underground mining and their interactions. Understanding the current tools and methodologies used in the mining industry for surface and underground mining options and transitions planning are essential to dealing with complex and deep-seated deposits that are amenable to both surface and underground mining. 
  • 3.1K
  • 29 Jul 2021
Topic Review
Palm Oil Background
Palm oil plantations cover millions of hectares worldwide, which encompass a significant portion of global trade. Palm oil trees, or Arecaceae, are a genus of stemless, tree-like monocot plants that thrive in the tropics and are extremely valuable to humans and the ecosystem. The African oil palm, or Elaeis guineensis, is the most prominent palm species native to West Africa, cultivated for its oil-rich fruit as a semiwild food source for over 7000 years. The tree produces a profusion of fruit bunches yearly with each containing between 1000 and 3000 fruits.
  • 3.1K
  • 14 Jul 2022
Topic Review
Massive Parallel Sequencing
Massive parallel sequencing or massively parallel sequencing is any of several high-throughput approaches to DNA sequencing using the concept of massively parallel processing; it is also called next-generation sequencing (NGS) or second-generation sequencing. Some of these technologies emerged in 1994-1998 and have been commercially available since 2005. These technologies use miniaturized and parallelized platforms for sequencing of 1 million to 43 billion short reads (50-400 bases each) per instrument run. Many NGS platforms differ in engineering configurations and sequencing chemistry. They share the technical paradigm of massive parallel sequencing via spatially separated, clonally amplified DNA templates or single DNA molecules in a flow cell. This design is very different from that of Sanger sequencing—also known as capillary sequencing or first-generation sequencing—that is based on electrophoretic separation of chain-termination products produced in individual sequencing reactions.
  • 3.1K
  • 29 Sep 2022
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